Tvis tick/knock

carina4age
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Tvis tick/knock

Postby carina4age » Fri Aug 03, 2018 3:19 am

I have horrible tvis knock in my 4age. First i thought that the noise was rod knock, put then i took off plug from tvis solenoid and the noise stopped instantly. Could vacuum be so weak that it cant hold butterflys closed or what?

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oldeskewltoy
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Re: Tvis tick/knock

Postby oldeskewltoy » Fri Aug 03, 2018 8:16 am

is it original? The TVIS mechanism could be badly worn, or someone might have serviced(disassembled/reassembled) it incorrectly.
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carina4age
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Re: Tvis tick/knock

Postby carina4age » Sat Aug 04, 2018 4:44 am

Yes it is, i have changed all vacuum lines and checked multiple times that they are correctly installed. I also checked and cleaned the butterflies and they looked good. And tvis works correctly, but the noise is horrible.

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jondee86
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Re: Tvis tick/knock

Postby jondee86 » Sat Aug 04, 2018 3:39 pm

So you have the same problem as this guy ??
https://www.youtube.com/watch?v=QYr9nloWzoM

You can check the vacuum servo (actuator) by using a hand pump like a Mityvac
and applying vacuum directly to the actuator. If the servo cannot hold vacuum and
leaks down in just a few seconds, then the diaphragm has split.

If the servo holds vacuum OK, then the next place to look is for excessive play in
the linkages. If the butterflys are free to move by even just one or two mm when
the servo has retracted, then intake pulsations will make the linkage rattle.

If you can find a way to get a length of string around the linkage so that you can
tie the butterflys firmly closed, then you can check if the noise goes away. Try this
first if you don't have a vacuum pump close by :)

Cheers... jondee86
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carina4age
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Location: Finland

Re: Tvis tick/knock

Postby carina4age » Sun Aug 05, 2018 2:22 am

Yes, problem is same :D i dont have vacuum pump so i try that tie method first